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A268772
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Number of nX6 0..2 arrays with some element plus some horizontally, vertically, diagonally or antidiagonally adjacent neighbor totalling two exactly once.
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1
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240, 620, 5214, 46312, 387146, 3104544, 24222418, 185142872, 1393319226, 10357051740, 76224579034, 556383657268, 4033179662378, 29064236056520, 208382539816438, 1487439977791192, 10576114792480666, 74940142727337224
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = 6*a(n-1) +51*a(n-2) -214*a(n-3) -1074*a(n-4) +2018*a(n-5) +7713*a(n-6) -10572*a(n-7) -22926*a(n-8) +30116*a(n-9) +25283*a(n-10) -32400*a(n-11) -15148*a(n-12) +15184*a(n-13) +5660*a(n-14) -2688*a(n-15) -1024*a(n-16) for n>18
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EXAMPLE
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Some solutions for n=4
..1..0..0..1..1..0. .2..2..2..1..2..1. .0..0..0..1..0..0. .1..2..2..2..2..1
..0..0..0..0..0..0. .2..2..2..2..2..2. .1..1..0..0..0..0. .2..1..2..2..2..2
..0..0..0..0..0..1. .1..2..2..1..2..1. .0..0..0..0..0..0. .2..2..2..2..2..2
..0..0..1..0..0..0. .2..2..2..2..2..1. .1..0..0..1..0..0. .1..2..1..2..2..2
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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